This April 2018 report on an investigation by the Interior Department’s Inspector General explains how workers on an offshore facility in the Gulf of Mexico faked a test of a critical piece of safety equipment known as a blowout preventer. A federal safety inspector indicated that this wasn’t an isolated incident. The safety inspector told investigators that, years earlier, when he was working in the industry, he learned how to create false tests results.

The report was obtained by the Project On Government Oversight through the Freedom of Information Act. It is accompanied by summaries of interviews conducted in the course of the investigation. Elements were redacted or withheld by the government.